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Community Member


Hi All


I have a strange scenario I need some help with.

We have purchased 6 sg500 52 port switches (one arrived faulty and has been rma'd) now I’m wondering if I don’t have another faulty switch.

I followed the following steps to configure them,


I have setup 3 sg500 52 with a stack (ring) 

Cable from sw1 S3 to sw3 S4

Cable from sw1 S4 to sw2 S3

Cable from sw2 S4 to sw3 S3

I forced sw1 as master.


Enable L3 routing.

Changed default VLAN to 10.

Created 3 additional VLANS 11, 12, 13.

Assigned respective IP to each VLAN.

Set the default route on the switch to point to the router.

Placed return paths from the firewall to the switch.


Then I started assigning ports to their respective VLAN, ie,

sw1 port 1-40 vlan 10 (untagged and other vlans exclude, this is set by default)

sw2 port 10-25 vlan 11 (untagged and other vlans exclude, this is set by default)

sw3 port 1-48 vlan 12 (untagged and other vlans exclude, this is set by default)


I assigned DHCP with the relevant address assignment to each vlan.


All machines on their respective vlan received the correct IP and there was communication between vlans for a period of time. After about an hour I could not access the switch stack unless I logged through the console (it did respond to Pings), machines lost access to internet and resources, so I reloaded the stack. Everything started working again for another 30 mins and it went down again.

I reset the whole lot and started from scratch went through the process of setting the stack up again and vlan config, this time I only had 15 machines connected to vlan 12 and again I lost access to the stack until I reloaded it….

At this point I reset the whole lot and left it running in standard switch mode.


Im wondering if there is a step I have left out or if I have another faulty switch.

Can anyone shed some light on this?

Everyone's tags (1)
Community Member

Hard to tell but here is what

Hard to tell but here is what you have to do when this happens again.

If you are getting response from the ping then open the Web interface and go to Administration/ System Mode and Stack Manager.

Check in there if you see all the units.

Or connect to the master and run Show stack all, and check you have connectivity into S3 and S3 of each unit.

If they don't have connectivity then you have to check the cables. Make sure that you don't have any other inter switch connectivity since this  might cause the block the other units as well due to Spanning tree.

Let me know what you find after this.

Btw, if the stack brakes do to no communication each unit will become master. Another question what does the led shows up when this happened?

Each stack units are identify by a unique led on the left, and the master has its own led.

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